I already said this in the comic thread but I like the theory so here goes...

Milo is eating a piece of chicken when he accidentally walks in on Charlie getting his undead freak on with someone (possibly Megan) in his shock Milo chokes to death on a chicken bone. This is of course why Jenny hates Charlie.

Are we even sure that Milo bites it on this trip out. Reading back the comic starts with the the fiasco on the first trip that Jenny is captain of the group but we aren't given a sure how many times they have been out with Charlie (unless I've missed it).

so with 11 motnhs to cover, I think Jenny could keep Milo alive indefinetly. At least another 200 - 300 updates.

When he returns in the Wastelands with the Zombie Hunters, Charlie throws a party with his old 'Zerker friends, after some time, Milo joins them, they all pass out sooner or later and when Charlie's friends wake up, they eat Milo because they are hungry and berzerkers so that's why Jenny hates Charlie.

Charlie isn't really a zerker. He's super smart zombie class and is just playing along the the whole half-life program is working. He's like a zombie double agent. Or I guess a triple agent since he originally was on the zombie side.

Jenny is swinging her shovel about with abandon, charlie gets shunted by a zumbah into jennys back, Bearhat flies onto milos FACE Milo stumbles into a group of crawlers and charlie accidently shoots milo.